Which one of the following is the context in which the term “qubit” is mentioned ?

The correct option is Quantum Computing.

In classical computing, the basic unit of information is a bit, which can represent a state of either 0 or 1. In contrast, quantum computing uses a quantum bit, or qubit, as its fundamental unit of information.
A qubit can exist in a state of 0, 1, or any quantum superposition of both states simultaneously. This property, along with quantum entanglement, allows quantum computers to process complex information at speeds exponentially faster than classical computers for certain tasks.